The use of mobile phones has become such an integral part of our daily lives that it would seem impossible to do without them nowadays. But the world, arguably, got by just as well before mobile phones were invented. For those brought up in the first half of the last century here, they went through times when a home telephone was a symbol of wealth. The numbers were also much easier to remember in those days, with a few digits and a prefix to show whether it was a number in Kowloon, the New Territories or Hong Kong Island.

But the arrival of mobile phones has revolutionised everything. From staying in touch with others to personal entertainment, from scouting information on the internet to taking selfies, and from online shopping to e-banking, hardly a day goes by without most of us using our smartphones.

Our insatiable appetite for mobile devices is reflected in the near-exhaustion of eight-digit phone numbers. According to estimates by the Office of the Communications Authority, there are currently 16.7 million phone numbers in use, with a registration rate of 145,000 per month. That means each Hongkonger has more than two mobile numbers in service. Although some five million new numbers are still available for use, they are expected to be exhausted in the next three years.

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Credit goes to the watchdog for tabling new measures to cope with the rising demand. These include reallocating some pager numbers as well as releasing numbers beginning with the digit 4, deemed inauspicious in Chinese culture due to its similar pronunciation with the word "death". The proposed measures could add another 15.7 million numbers and maintain the eight-digit regime until 2028.